OE 18. Module Optflow

Introduce a separate optflow module with up-to-date algorithms

• Author: Vadim Pisarevsky
• Link: The feature request
• Status: Draft
• Platforms: All
• Complexity: 1-2 man-weeks

Introduction and Rationale

The module video from OpenCV 2.x and 3.x includes various functionality including sparse and dense optical flow algorithms. At the same time, there is experimental optflow module in opencv_contrib that includes some new optical flow algorithms. It makes sense to consolidate optical flow estimation algorithm into a dedicated module.

Proposed solution

Create a dedicated optflow module in the main repository with the best available (within the library) collection of sparse and dense optical flow algorithms. For the sparse optical flow we have LK optical flow and maybe some experimental semi-dense optical flow somewhere that we can put it. As for the dense optical flow, we have more or less classical Farneback algorithm and we have much better DIS optical flow. We need to compare them all and select the best algorithms.

We will also need to shape all the optical flow algorithms as classes derived from the base sparse or dense optical flow estimators. Some attempts to do that can already be found in video module.

We also need to rename optflow module in opencv_contrib to something else (let's move away from xmodule naming scheme in opencv_contrib)

Impact on existing code, compatibility

Even though we consolidate API and move to the uniform object-oriented API, we may keep the old API for backward compatibility (e.g. cv::computeOptFlowFarneback etc.).

Possible alternatives

nothing really; we need to consolidate optical flow code.

References

TBD